全文获取类型
收费全文 | 67671篇 |
免费 | 5496篇 |
国内免费 | 1800篇 |
专业分类
耳鼻咽喉 | 110篇 |
儿科学 | 939篇 |
妇产科学 | 261篇 |
基础医学 | 2922篇 |
口腔科学 | 290篇 |
临床医学 | 12582篇 |
内科学 | 21546篇 |
皮肤病学 | 200篇 |
神经病学 | 1930篇 |
特种医学 | 2478篇 |
外国民族医学 | 4篇 |
外科学 | 4454篇 |
综合类 | 12363篇 |
现状与发展 | 6篇 |
预防医学 | 5283篇 |
眼科学 | 71篇 |
药学 | 5935篇 |
141篇 | |
中国医学 | 2630篇 |
肿瘤学 | 822篇 |
出版年
2024年 | 56篇 |
2023年 | 1198篇 |
2022年 | 1567篇 |
2021年 | 3059篇 |
2020年 | 3168篇 |
2019年 | 2496篇 |
2018年 | 2458篇 |
2017年 | 2383篇 |
2016年 | 2664篇 |
2015年 | 2773篇 |
2014年 | 5719篇 |
2013年 | 5826篇 |
2012年 | 4941篇 |
2011年 | 4954篇 |
2010年 | 3802篇 |
2009年 | 3383篇 |
2008年 | 3314篇 |
2007年 | 3451篇 |
2006年 | 2808篇 |
2005年 | 2380篇 |
2004年 | 1831篇 |
2003年 | 1500篇 |
2002年 | 1266篇 |
2001年 | 1106篇 |
2000年 | 825篇 |
1999年 | 670篇 |
1998年 | 642篇 |
1997年 | 593篇 |
1996年 | 421篇 |
1995年 | 526篇 |
1994年 | 425篇 |
1993年 | 397篇 |
1992年 | 331篇 |
1991年 | 296篇 |
1990年 | 227篇 |
1989年 | 204篇 |
1988年 | 203篇 |
1987年 | 171篇 |
1986年 | 133篇 |
1985年 | 175篇 |
1984年 | 131篇 |
1983年 | 84篇 |
1982年 | 104篇 |
1981年 | 84篇 |
1980年 | 51篇 |
1979年 | 52篇 |
1978年 | 29篇 |
1977年 | 31篇 |
1976年 | 20篇 |
1975年 | 21篇 |
排序方式: 共有10000条查询结果,搜索用时 218 毫秒
101.
Dawn S. Hui Richard Lee Marc R. Moon Melanie A. Edwards Mina L. Boutrous Jessica G.Y. Luc Richard L. Prager Keith S. Naunheim 《The Journal of thoracic and cardiovascular surgery》2019,157(5):1925-1932
Background
In cardiothoracic surgery, little data exist on the transition to operative independence. We aimed to compare current perceptions of operative autonomy of junior cardiothoracic surgeons and senior colleagues who oversee transitional years.Methods
An anonymous online survey was sent to currently practicing North American board-certified/eligible cardiothoracic surgeons to assess reported time to operative independence and comfort with cardiothoracic operations. The χ2 test, Fisher exact test, and Mann-Whitney U test were used to compare junior surgeons’ self-reported experience to the junior experience as reported by the midcareer and senior surgeons with whom they practiced. Logistic regression was performed to assess factors associated with operative independence.Results
Responses from 436 completed surveys were analyzed (82 juniors and 354 midcareer/seniors). Two hundred fifty-four midcareer/senior surgeons reported on the experience of 531 junior partners. Juniors reported high immediate posttraining comfort with basic cardiac cases and moderate comfort with all other categories. Time to operative independence was significantly different between juniors' self-report and midcareer/senior reports of junior partners except for complex thoracic cases. In multivariable logistic regression analysis, senior, and not midcareer, surgeon status was independently associated with junior operative independence status for cardiac cases and for basic thoracic cases.Conclusions
Most junior surgeons perceived operative independence with basic thoracic, basic cardiac, and complex cardiac operations earlier in their surgical career than that reported by senior colleagues. Objective measures of operative independence may clarify this discrepancy. This study establishes a baseline by which to compare the effects of integrated 6-year programs on operative independence. The discrepant perceptions may have implications for how training programs prepare graduates for the transition to independent practice. 相似文献102.
103.
Milan Milojevic Patrick W. Serruys Joseph F. Sabik David E. Kandzari Erick Schampaert Ad J. van Boven Ferenc Horkay Imre Ungi Samer Mansour Adrian P. Banning David P. Taggart Manel Sabaté Anthony H. Gershlick Andrzej Bochenek Jose Pomar Nicholas J. Lembo Nicolas Noiseux John D. Puskas Arie Pieter Kappetein 《Journal of the American College of Cardiology》2019,73(13):1616-1628
Background
The randomized EXCEL (Evaluation of XIENCE versus Coronary Artery Bypass Surgery for Effectiveness of Left Main Revascularization) trial reported a similar rate of the 3-year composite primary endpoint of death, myocardial infarction (MI), or stroke in patients with left main coronary artery disease (LMCAD) and site-assessed low or intermediate SYNTAX scores treated with percutaneous coronary intervention (PCI) and coronary artery bypass grafting (CABG). Whether these results are consistent in high-risk patients with diabetes, who have fared relatively better with CABG in most prior trials, is unknown.Objectives
In this pre-specified subgroup analysis from the EXCEL trial, the authors sought to examine the effect of diabetes in patients with LMCAD treated with PCI versus CABG.Methods
Patients (N = 1,905) with LMCAD and site-assessed low or intermediate CAD complexity (SYNTAX scores ≤32) were randomized 1:1 to PCI with everolimus-eluting stents versus CABG, stratified by the presence of diabetes. The primary endpoint was the rate of a composite of all-cause death, stroke, or MI at 3 years. Outcomes were examined in patients with (n = 554) and without (n = 1,350) diabetes.Results
The 3-year composite primary endpoint was significantly higher in diabetic compared with nondiabetic patients (20.0% vs. 12.9%; p < 0.001). The rate of the 3-year primary endpoint was similar after treatment with PCI and CABG in diabetic patients (20.7% vs. 19.3%, respectively; hazard ratio: 1.03; 95% confidence interval: 0.71 to 1.50; p = 0.87) and nondiabetic patients (12.9% vs. 12.9%, respectively; hazard ratio: 0.98; 95% confidence interval: 0.73 to 1.32; p = 0.89). All-cause death at 3 years occurred in 13.6% of PCI and 9.0% of CABG patients (p = 0.046), although no significant interaction was present between diabetes status and treatment for all-cause death (p = 0.22) or other endpoints, including the 3-year primary endpoint (p = 0.82) or the major secondary endpoints of death, MI, or stroke at 30 days (p = 0.61) or death, MI, stroke, or ischemia-driven revascularization at 3 years (p = 0.65).Conclusions
In the EXCEL trial, the relative 30-day and 3-year outcomes of PCI with everolimus-eluting stents versus CABG were consistent in diabetic and nondiabetic patients with LMCAD and site-assessed low or intermediate SYNTAX scores.(Evaluation of XIENCE versus Coronary Artery Bypass Surgery for Effectiveness of Left Main Revascularization [EXCEL]; NCT01205776) 相似文献104.
IntroductionOne of the current harm reduction debates in Australia concerns the legalisation of the extended distribution of sterile needles and syringes, a practice that is currently unlawful in most Australian settings.MethodsWe used data from a unique pilot program of authorised extended distribution to document the opinions held by 22 key stakeholders -service staff, drug users and police - about the risks and benefits of authorisation, and to analyse the ways in which drug users were understood within these.ResultsOpinions were strongly in favour of authorising extended distribution, based on the belief that this would reduce the transmission of hepatitis C. However, stakeholders also identified that distributors risked attention from police and some noted that the consequences of this would be borne by distributors themselves and not the services that support them. These opinions rested on specific assumptions about people who inject, some of which reflect negative constructions of drug users as a source of danger to the public or as helpless ‘addicts’ with little control over their risk reduction. But there were other representations that positioned drug users more positively as responsible agents with a strong duty of care to themselves and others whose choices are often limited by inadequate service structures. Staff participants drew on these understandings in careful and strategic ways, arguing for the rationality and expertise of drug users, while also problematizing the individualised approach that any form of authorised extended distribution might take.ConclusionWe argue that localised and incremental changes such as those that took place to support this pilot project, and the extensive support for extended distribution among stakeholders in this study including police, creates meaningful opportunities to think about extended distribution differently, which can in turn support conditions for future discussions about legislative change. 相似文献
105.
Topical Treatment of Oral Mucositis in Cancer Patients: A Systematic Review of Randomized Clinical Trials 下载免费PDF全文
Geisa Sant AnaAna Gabriela Costa NormandoIsabela de Toledo Paula Elaine Diniz dos ReisEliete Neves Silva Guerra 《Asian Pacific journal of cancer prevention》2020,21(7):1851-1866
Background and Purpose: Evidence-based protocols of topical therapy for oral mucositis (OM) induced by chemoradiotherapy (CRT) are continuously established and updated. Thus, the present systematic review aims to evaluate the scientific literature in terms of effectiveness of topical treatment of OM in cancer patients undergoing CRT. Materials and Methods: This systematic review was based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) Checklist. Randomized clinical trials were identified through electronic database searches on CINAHL, Cochrane Library, LILACS, Livivo, PubMed, SCOPUS, and Web of Science. Grey literature was also assessed on Google Scholar, Open Grey, and ProQuest. The risk of bias in the included studies was assessed by the Cochrane Collaboration Risk of Bias Tool. Results: Twenty-three randomized clinical trials (n=1169 patients) met the inclusion criteria. Twenty-three different topical agents were examined and categorized into five groups: analgesics (30.4%), natural agents (21.7%), other topical agents (21.7%), antimicrobial agents (17.4%), and growth factors (8.8%). Of the included studies, 50% presented a resolution of OM within 14 days. Topical natural agents yielded good results with average resolution time of 3–7 days. The included studies generally demonstrated that patients treated with mouthwashes presented superior benefits compared to the control, depending on OM severity. Conclusion: Topical agents effectively reduced the severity of OM lesions and pain intensity in patients receiving chemoradiotherapy, although the effects varied by agent type. However, the heterogeneity in the results of these topical intervention studies underscores the need for standardized clinical trial methodologies. Clinical Relevance: Topical agents were effective in patients with severe OM lesions receiving chemoradiotherapy and are a good alternative of home care in relation to pain control, reduction of inflammation and consequent improvement in quality of life. 相似文献
106.
107.
目的:系统性评价替格瑞洛对比氯吡格雷治疗东亚急性冠状动脉综合征(ACS)患者的有效性和安全性,旨在为临床用药提供循证参考。方法:计算机检索Cochrane图书馆、PubMed、Embase、中国知网、万方数据库等,收集替格瑞洛(试验组)对比氯吡格雷(对照组)治疗东亚ACS患者的随机对照试验(RCT)。筛选文献、提取数据后采用Cochrane系统评价员手册5.1.0推荐的偏倚风险评估工具对纳入文献进行质量评价,采用Rev Man 5.3统计软件进行Meta分析。结果:共纳入5项RCT,共计4511例患者。Meta分析结果显示,两组患者主要心血管不良事件发生率[OR=0.85,95%CI(0.68,1.04),P=0.12]、心血管原因死亡率[OR=0.76,95%CI(0.57,1.03),P=0.08]、脑卒中发生率[OR=0.77,95%CI(0.48,1.24),P=0.28]比较,差异均无统计学意义;试验组患者主要出血事件发生率[OR=1.54,95%CI(1.19,1.99),P=0.001]、次要出血事件发生率[OR=1.80,95%CI(1.40,2.32),P<0.00001]均显著高于对照组。结论:替格瑞洛在降低东亚ACS患者的主要心血管不良事件、心血管原因死亡以及脑卒中的发生风险等方面的作用与氯吡格雷相当,但该药会增加患者主要出血、次要出血事件的发生风险。 相似文献
108.
109.
110.
《The Journal for Nurse Practitioners》2020,16(1):79-82
The objective of this quality improvement project was to increase human papillomavirus (HPV) vaccine initiation rates among males aged 11 to 21 years old. A multipronged strategy was implemented at a pediatric practice, including an electronic medical record prompt, educational presentation, and monthly e-mail updates to providers. Deidentified HPV vaccine initiation rate data were collected, and a paired 2-sample t test evaluated differences in prepost vaccine initiation rates. HPV vaccine initiation rates increased by 6.5% during the project period. The medical record prompt was identified as most effective by 75% of participating providers. Small gains can be made to improve HPV vaccine initiation rates among adolescent males. 相似文献